There is a great need for devices or apparatuses which make it possible to identify or detect, as regards their presence at a predetermined location, objects which are provided with such devices or apparatuses in contactless manner and over a certain distance. An additional need exists to be able to simultaneously identify or detect, as regards their presence at a predetermined location, groups of objects having some common identifying feature which are provided with such devices or apparatuses in contactless manner and over a certain distance.
It is for example desirable to request contactless and over a certain distance identifications which are uniquely assigned to a group of objects and which are stored in the devices or apparatuses so that it can be determined whether at least one of the group of objects is at a predetermined location. An example is within a production, warehouse, or commercial environment in which physical characteristics such as product type, color, or customer destination are to be interrogated directly at or in the object without direct access to the object being possible. To accomplish these ends using prior art systems, a search would be initiated using a central database containing at least the information of which unique transponders are available. By way of example, with this method in order to determine all locations for a group of 100 member transponders it would be necessary to initiate 100 lookups in the database and perform 100 searches for the member transponders.